Except that’s now how the sanctions are tailored. The US also reserve the right to fine any company with ties to the US. That’s a basic part of US justice and, more importantly, US administration: Find any tie, sometimes ludriciously so, to the US and you can sue in the US under US law.
You can see that any time a large public transport accident happens and the US lawyers fly in, trying to find an angle to sue in the US.